Telomeres are protective structures at the ends of eukaryotic chromosomes. The loss of telomeres through cell division and oxidative stress is related to cellular aging, organismal growth and disease. In this way, tel...Telomeres are protective structures at the ends of eukaryotic chromosomes. The loss of telomeres through cell division and oxidative stress is related to cellular aging, organismal growth and disease. In this way, telomeres link molecular and cellular mechanisms with organismal processes, and may explain variation in a number of important life-history traits. Here, we discuss how telomere biology relates to the study of physiological ecology and life history evolution. We emphasize current knowledge on how telomeres may relate to growth, survival and lifespan in natural populations. We finish by examining interest- ing new connections between telomeres and the glucocorticoid stress response. Glucocorticoids are often employed as indices of physiological condition, and there is evidence that the glucocorticoid stress response is adaptive. We suggest that one way that glucocorticoids impact organismal survival is through elevated oxidative stress and telomere loss. Future work needs to establish and explore the link between the glucocorticoid stress response and telomere shortening in natural populations. If a link is found, it provides an explanatory mechanism by which environmental perturbation impacts life history trajectories [Current Zoology 56 （6）： 714-727, 2010].展开更多
Through systematic analysis and comparison of the common features of SAA, ES and traditional LS (local search) algorithm, a new hybrid strategy of mixing SA, ES with LS, namely HIEA (Hybrid Intelligent Evolutionary Al...Through systematic analysis and comparison of the common features of SAA, ES and traditional LS (local search) algorithm, a new hybrid strategy of mixing SA, ES with LS, namely HIEA (Hybrid Intelligent Evolutionary Algorithm), is proposed in this paper. Viewed as a whole, the hybrid strategy is also an intelligent heuristic searching procedure. But it has some characteristics such as generality, robustness, etc., because it synthesizes advantages of SA, ES and LS, while the shortages of the three methods are overcome. This paper applies Markov chain theory to describe the hybrid strategy mathematically, and proves that the algorithm possesses the global asymptotical convergence and analyzes the performance of HIEA.展开更多
The focus of the article is on the contribution of the perspective of supply chain management （SCM） to the explanation of internationalization processes. The empirical study is based on case studies of 20 small- and...The focus of the article is on the contribution of the perspective of supply chain management （SCM） to the explanation of internationalization processes. The empirical study is based on case studies of 20 small- and medium-sized enterprises （SMEs） with international activities from China, India, New Zealand, and Singapore. All chosen firms were founded after 1980 in order to capture retrospectively the whole globalization process of each firm. All sample firms operate their supply chains （SCs） on the basis of information and communications technology （ICT）. Depending on size, strategy, business model, industry, and mindset of the managers, firms use ICT on a range from integrating individual functional areas to integrating the whole SC through enterprise resource planning （ERP） and customer relationship management （CRM） systems.展开更多
文摘Telomeres are protective structures at the ends of eukaryotic chromosomes. The loss of telomeres through cell division and oxidative stress is related to cellular aging, organismal growth and disease. In this way, telomeres link molecular and cellular mechanisms with organismal processes, and may explain variation in a number of important life-history traits. Here, we discuss how telomere biology relates to the study of physiological ecology and life history evolution. We emphasize current knowledge on how telomeres may relate to growth, survival and lifespan in natural populations. We finish by examining interest- ing new connections between telomeres and the glucocorticoid stress response. Glucocorticoids are often employed as indices of physiological condition, and there is evidence that the glucocorticoid stress response is adaptive. We suggest that one way that glucocorticoids impact organismal survival is through elevated oxidative stress and telomere loss. Future work needs to establish and explore the link between the glucocorticoid stress response and telomere shortening in natural populations. If a link is found, it provides an explanatory mechanism by which environmental perturbation impacts life history trajectories [Current Zoology 56 （6）： 714-727, 2010].
文摘Through systematic analysis and comparison of the common features of SAA, ES and traditional LS (local search) algorithm, a new hybrid strategy of mixing SA, ES with LS, namely HIEA (Hybrid Intelligent Evolutionary Algorithm), is proposed in this paper. Viewed as a whole, the hybrid strategy is also an intelligent heuristic searching procedure. But it has some characteristics such as generality, robustness, etc., because it synthesizes advantages of SA, ES and LS, while the shortages of the three methods are overcome. This paper applies Markov chain theory to describe the hybrid strategy mathematically, and proves that the algorithm possesses the global asymptotical convergence and analyzes the performance of HIEA.
文摘The focus of the article is on the contribution of the perspective of supply chain management （SCM） to the explanation of internationalization processes. The empirical study is based on case studies of 20 small- and medium-sized enterprises （SMEs） with international activities from China, India, New Zealand, and Singapore. All chosen firms were founded after 1980 in order to capture retrospectively the whole globalization process of each firm. All sample firms operate their supply chains （SCs） on the basis of information and communications technology （ICT）. Depending on size, strategy, business model, industry, and mindset of the managers, firms use ICT on a range from integrating individual functional areas to integrating the whole SC through enterprise resource planning （ERP） and customer relationship management （CRM） systems.
